HPLC-ELSD和GC-FID测定中长链甘油三酯含量比较研究

Comparison of determination of medium- and long- chain triacylglycerol by HPLC- ELSD and GC- FID

采用间接法定量,建立了HPLC-ELSD外标法和GC-FID内标法测定中长链甘油三酯含量的方法,并对两种方法进行比较。结果表明:两种方法在各自的质量浓度范围内均具有良好的线性关系,HPLC-ELSD外标法测定辛癸酸甘油酯和大豆油的平均加标回收率分别为101.0%和99.5%,RSD分别为1.58%和1.62%,得到酯交换产物中中长链甘油三酯含量为72.8%±0.80%;GC-FID内标法测定辛癸酸甘油酯和大豆油的平均加标回收率分别为99.4%和99.6%,RSD分别为1.24%和2.03%,得到酯交换产物中中长链甘油三酯含量为72.5%±0.84%。说明两种分析方法均具有良好的精密度和重复性。HPLC-ELSD外标法的分析时间为43 min,GC-FID内标法分析时间仅需12.7 min。

Using indirect method, the quantitative determination of contents of medium - and long - chain triacylglycerol （MLCT） was studied by HPLC -ELSD external standard and GC -FID internal standard methods. And the two methods were compared. The results showed that both of the two methods had good linear relationships in the range of their respective mass concentration. The average recoveries of standard addition of caprylic/capric triglyceride and soybean oil determined by HPLC - ELSD external standard method were 101.0% and 99.5% separately, the RSDs were 1.58% and 1.62% respectively, and the MLCT content in the transesterification product was 72.8% ± 0.80%. The average recoveries of standard addition of caprylic/capric triglyceride and soybean oil determined by GC -FID internal standard method were 99.4% and 99.6% separately, the RSDs were 1.24% and 2.03% respectively, and the MLCT con- tent in the transesterification product was 72.5% ±0.84%. Both the two methods had good precision and repeatability. The analysis time of HPLC - ELSD external standard method was 43 rain, while GC - FID in-ternal standard method only needed 12.7 min.